The excessive consumption of potable water remains a dilemma for water agencies, commercial building owners, homeowners, residents and sanitaryware manufacturers. An increasing global population has negatively affected the amount and quality of suitable water. Effluents in water supplies and increasing air pollutants have drastically altered fresh water supplies. The propensity for drought in previously fertile geographies has reinforced global concern over responsible water consumption. The drive for optimum water conservation strategies, however, typically yields to the overriding need to sustain a healthy population through the enactment and enforcement of plumbing codes and the installation of sanitary plumbing fixtures that are compliant therewith.
In an effort to execute water conservation strategies, many sanitaryware manufacturers have introduced a variety of low water and water-free urinals. Waterless urinals are available that often employ replaceable cartridges. The cartridges have means for entry and discharge and a sealant layer that prevents malodorous emissions from the drainage system yet allows flow of urine therethrough. Conventional waterless designs, however, do not scour a back wall surface and do not provide a water trap seal as required by plumbing codes in the United States and other jurisdictions. In addition, omission of the water trap seal in waterless fixtures necessarily omits replenishment of the trap seal after each use, thereby requiring frequent maintenance of the fixtures to maintain satisfactory cleanliness (such as the addition of a liquid medium to provide a seal between the liquid waste and the room, and periodic cartridge replacement). Examples of such devices are disclosed in U.S. Pat. Nos. 6,053,197, 6,425,411, 5,711,037 and US Patent Application Nos. 2002/0069913 and 2002/0038474.
In addition, many conventional low-water urinals have strategically designed bowls and trapways that restrict elimination of water from the bowl during flushing (see, for example, U.S. Pat. Nos. 4,310,934 and 5,386,596). Such designs, however, still use an inordinate amount of water to complete a flush cycle, especially in consideration of contemporary water conservation efforts. Other well-known conventional designs use a manifold with integral holes at the top of the urinal to distribute water around the inside top perimeter. The manifold comprises an additional chinaware piece in the construction of the urinal, thereby increasing manufacturability efforts and costs. Such manifolds do not produce a uniform distribution and typically are not pressurized; such devices employ a “gravity fed” technique that and trickles down the sides of the urinal at low velocity along a uniform path. Such configurations exhibit disadvantageous hygiene limitations by omitting fluid coverage over the entirety of the urinal's waste receiving surface.
Other manufacturers have used sensor means to release water at predetermined intervals, thereby providing a dual or multi-flush urinal for maintenance of sanitary conditions with minimal water consumption. For instance, U.S. Pat. No. 6,862,754 to DeMarco (“DeMarco”) discloses a dual-phase flush urinal comprising a chinaware piece in combination with a valve means (DeMarco is owned by American Standard International Inc., co-owner of the present application, and is incorporated by reference herein). The valve means is in electrical communication with a sensor that detects the presence of a user and has first and second fluid discharge ports, wherein the first fluid discharge port is in fluid communication with a bowl portion defined in the chinaware. Upon detection of the user, the sensor transmits a first signal to the valve means to initiate a first water exchange phase of the flush cycle. The first fluid discharge port provides water along an elongate channel to remove waste from the bowl portion. After a preprogrammed delay, the sensor transmits a second signal to the valve means to initiate a subsequent, time-delayed wall-scouring phase of the flush cycle. The second fluid discharge port provides water through a urinal spreader to ensure rinsing of the back surface subsequent to actuation of the jet. The valve means operates according to a desired preprogrammed schedule to ensure delivery of adequate water to the urinal jet and expulsion of waste from the urinal to an exterior sewage system.
It is therefore desirable to provide a urinal that substantially reduces consumption of portable water without comprising sanitation. Such a urinal uses minimal water amounts to achieve an effective, repeatable flush and thereby maintain optimal fixture cleanliness.